Method and apparatus for making flexible strips of material having a pile of hook-shaped elements

ABSTRACT

A method is disclosed for making the hook or loop part of a separable hook and loop type fastener by bending a flexible base strip having a plurality of unbroken hook-shaped rails protruding from one surface thereof into a generally tubular form with the rails extending radially inwardly thereof; and thereafter progressively subjecting spaced-apart cross-sectional segments of each rail alternately and periodically to a rotational cutting action to transform each rail into a row of individually spacedapart resilient hooks or loops.

United States Patent Erb [54] METHOD AND APPARATUS FOR MAKING FLEXIBLESTRIPS OF MATERIAL HAVING A PILE OF HOOK- SHAPED ELEMENTS [72] Inventor:George H. Erb, Rutland, Vt.

[73] Assignee: American Velcro, Inc.

[22] Filed: Nov. 18, 1970 [21] Appl. No.: 90,710

[52] US. Cl ..29/4l0, 29/558 [51] Int. Cl. ..B2ld 53/52, B23p 13/04 [58]Field ofSearch ..29/410,558, 557,2075

[ 51 May 30, 1972 [56] References Cited UNITED STATES PATENTS 3,290,74712/ 1966 Burbank ..29/4l0 X Primary Examiner-Thomas l-l. EagerArtamey-Pennie, Edmonds, Morton, Taylor & Adams ABSTRACT A method isdisclosed for making the hook or loop part of a separable hook and looptype fastener by bending a flexible base strip having a plurality ofunbroken hook-shaped rails protruding from one surface thereof into agenerally tubular form with the rails extending radially inwardlythereof; and thereafter progressively subjecting spaced-apartcross-sectional segments of each rail alternately and periodically to arotational cutting action to transform each rail into a row ofindividually spaced-apart resilient hooks or loops.

7 Claims, 9 Drawing Figures INVENTOR. GE ORGE H. ERB /%fzl%i ATTORNEYPATENTED mm 30 I972 SHUT 10? 3 sum 2 0F 3 DDODUDDDDUU .uDDUDOUDU-u mPATENTEDMAY 30 mm EoR E fi i? B ATTORNEYS PATENTEUmmo m2 3, 685,584

SH'LEI 3G? 3 FIG. 6

FIG. 8

INVENTOR. GEORGE H. ERB M ATTORNEYS METHOD AND APPARATUS FOR MAKINGFLEXIBLE STRIPS OF MATERIAL HAVING A FILE OF HOOK- SI-IAPED ELEMENTSBACKGROUND OF THE INVENTION- This invention relates to separablefastening devices of the type wherein one part of the fastener has amultiplicity of small outwardly projecting loops of thin filamentarymaterial and the other surface is provided with a multiplicity of curledor hook-like resilient projections. Such fasteners have been describedin U. S. Pat. Nos. 2,717,437 and 3,009,235.

It will be understood that when two layers of this type are pressed intoface-to-face contact, their respective hooks and loops interengage onewithin the other thereby securing said layers into locking engagement.Separation of the two layers requires a force of considerable magnitudewhen attempting to effect the separation of a large number of hooks andloops at once, but separation may be quite readily effected byprogressively peeling the layers apart.

Fastenersconstructed with interlocking hooks and loops of the typedescribed find a wide variety of applications. For instance, they can besubstituted for existing closing devices such as buttons, buckles,clasps, slidable fasteners of the type popularly termed zippers, or likeattachments which are currently used in many diverse type of wearingapparel. In addition, they serve a useful function in many particularenvironments where it is desired to fasten one object to another in aquick and efficient manner.

In the past, the hooked surface of these fasteners has been formed bysubjecting a multiplicity of loops to the cutting action of a deviceconsisting of a comb of tapered needles having mounted thereon smallrapidly reciprocating scissors-like cutters which clip each loop at apre-determined point thereby resulting in a hook and stub formationwhich, due to the resilient nature of the filamentary loops, to a greatextent resembles a snap hook configuration.

It is a principal object of this invention to provide an alternatemethod for producing a hooked surface of the type described whichfurther utilizes an extruded starting material employing severalpossible hook-like forms or alternatively a loop form.

SUMMARY OF THE INVENTION In accordance with the teachings of the presentinvention, a length of flexible base material, in the form of anextruded strip or tape of any suitable composition, is provided with aplurality of upstanding integral rails extending generally lengthwise ofthe strip. Each rail has either a hook-shaped or loop-shapedcross-sectional configuration. The strip is bent into a generallytubular form with the upstanding rails projecting radially inwardlythereof. In this condition, each rail is subjected alternately to atranslatory rotational cutting action wherein selected spaced-apartcross-sectional segments of each inwardly extending rail areperiodically removed to transform each rail into a row of individuallyspaced-apart resilient hooks or into rows of loops.

BRIEF DESCRIPTION OF THE DRAWING FIG. 1 is a perspective view of thestarting tape according to the invention;

FIG. la is a cross-sectional view taken in the direction of arrows lalaofFIG. 1;

FIG. 2 is an elevational view of the starting tape of FIG. 1 formed intoa tube and subjected to internal cutting by an apparatus;

FIG. 3 is a top view of the starting tape and apparatus of FIG. 2;

FIG. 4 is a cross-section taken in the direction of arrows 4- 4 ofFIG.2;

FIG. 5 is a fragmentary perspective view of the hook fastener tapematerial produced according to the present invention; and

FIGS. 6--8 are cross-sections of tape material showing differentconfigurations of hook and loop elements formed in accordance with thepresent invention.

DESCRIPTION OF PREFERRED EMBODIMENTS With reference initially to FIGS. 1and la of the drawing there has been disclosed a starter material 10having a backing l1 and a series of rails 12 extending therefrom. In theillustrated embodiment the rails (as shown in FIG. 1a) are hooklikeextensions which are integral with the backing rail 1 l and are extrudedintegrally therewith of a suitable plastic material.

Referring to FIG. 2, the starter material 10 is passed along an endlessbelt 14 through a frusto-conical shaped forming die 16 which causes thestarter material 10 gradually to be formed into a generally tubularshape. As the starter material moves in an axial direction in thedirection of arrow 17, it will gradually ride up on the taperingcircular inner surface of the die 16 to emerge from the smaller end 16ain a generally tubular form. The diameter of the smaller end of the dieis slightly larger than the diameter of the circle which would be formedif the side edges 11a and 11b were brought into abutting contact.

This arrangement provides a tubular form with a gap which permits thetubular form to pass without interference with the gear belt 21connecting the cutter 20 to the motor 22. The cutter 20 is formed as ahelix so that as the starter material 11 progresses past the cutter, therails 12 will be cut progressively and will produce a series ofupstanding hooks as shown in FIG. 5. In the particular, illustratedembodiment, there has been provided a cooling means schematicallyindicated as surrounding the forrning die 16 which will increase therigidity of rails 12 so that these may be cut more readily. Aftercutting, the material 10 and hooks 12a will pass through a suitableheating means 36 which will return the material to its original orambient temperature.

It should be noted that the term hook-shaped rail" as used in thespecification and claims is intended to signify any upstanding unbrokenrail which when out in the manner herein disclosed will produce a row ofindividual, spaced apart, and upstanding elements which are suitable foruse as the hooks of the hook member of a hook and loop type separablefastener. For instance, as shown in FIG. 6 upstanding rails 24 areshaped respectively as arrowheads, and in FIG. 7 the rails 25 are formedas double-hooks.

In the foregoing description of this invention, reference has been madeto the fact that the transverse bending of the starting tape into atubular form and movement of the tubular form longitudinally inpartially encircling relationshipto the fixed rotary cutter isaccomplished simultaneously. It should be noted, however, that thesesteps may be performed sequentially. Thus, the starting tape may be bentinto a generally tubular form and secured in a fixed position on astationary table. Thereafter the rotating cutter may be moved axiallythrough the tubular form to remove spaced-apart cross-sectional segmentsof each rail in the manner described above. Alternatively, the startingtape may be first bent into a tubular form and thereafter moved past afixed rotating cutter in partial encircling relationship thereto, toproduce the ultimate hooks. It should further be appreciated that whilebending of the material into tubular form is a preferred method,nevertheless the material can be cut in accordance with the broadprinciples of the invention while it is flat.

It should also be understood that while the method herein disclosed hasbeen described with particular reference to producing the hook member ofa separable hook and loop type fastener, it should also be recognizedthat the method of this invention is equally well suited to producingthe loop member of a separable hook and loop type fastener. When themethod of this invention is so used, the upstanding hookshaped rails maybe merely replaced by a series of unbroken and upstanding loop-shapedrails 26 shown in FIG. 8.

While a preferred specific embodiment of the invention has beenheretofore described, it is to be clearly understood that variousmodifications, in addition to those specifically mentioned, can be madein the details of the invention described herein without departing fromthe spirit of the invention and the scope of the appended claims.

What is claimed is:

1. A method for making the hook member of a separable hook and loop typefastener comprising:

a. providing a base material with a plurality of upstandingspaced-apart, and unbroken rails extending lengthwise of said basematerial, each rail having a generally hook or loop shapedcross-sectional configuration;

b. progressively cutting away spaced-apart cross-sectional segments ofeach rail to thereby transform each rail into a row of individualspacedapart hooks or loops.

2. The method according to claim 1 wherein said base material is cooledin order to make said rails more rigid prior to cutting said segments.

3. The method according to claim 1 wherein said base material is benttransversely into tubular form with said rails extending radiallyinwardly thereof prior to cutting said rails.

4. The method according to claim 3 wherein the step of cutting away saidsegments is accomplished by subjecting each rail alternately andperiodically while in said tubular form to the rotational cutting actionof a rotary cutter disposed within said tubular form, said cutter beingadapted to remove selected spaced-apart cross-sectional segments of eachrail upon contact therewith.

5. The method according to claim 4 wherein said tubular form is fixedwith respect to said rotating cutter, said rotating cutter being movedaxially through said tubular form to alternately and periodically cutaway spaced-apart cross-sectional segments of each rail to form said rowof individual spaced-apart hooks or loops.

6. The method according to claim 4 wherein said rotating cutter isfixedin a translational sense with said tubular form being moved past saidrotating cutter in at least a partially en-' circling relationshipthereto, thereby cutting away spacedapart cross-sectional segments ofeach rail to form said rows of hooks or loops 7. The method according toclaim 6'wherein the steps of bending the base material and cutting awayspaced-apart cross-sectional segments of each rail are performedsubstantially simultaneously with each other.

i i i

1. A method for making the hook member of a separable hook and loop typefastener comprising: a. providing a base material with a plurality ofupstanding spaced-apart, and unbroken rails extending lengthwise of saidbase material, each rail having a generally hook or loop shapedcross-sectional configuration; b. progressively cutting awayspaced-apart cross-sectional segments of each rail to thereby transformeach rail into a row of individual spaced-apart hooks or loops.
 2. Themethod according to claim 1 wherein said base material is cooled inorder to make said rails more rigid prior to cutting said segments. 3.The method according to claim 1 wherein said base material is benttransversely into tubular form with said rails extending radiallyinwardly thereof prior to cutting said rails.
 4. The method according toclaim 3 wherein the step of cutting away said segments is accomplishedby subjecting each rail alternately and periodically while in saidtubular form to the rotational cutting action of a rotary cutterdisposed within said tubular form, said cutter being adapted to removeselected spaced-apart cross-sectional segments of each rail upon contacttherewith.
 5. The method according to claim 4 wherein said tubular formis fixed with respect to said rotating cutter, said rotating cutterbeing moved axially through said tubular form to alternately andperiodically cut away spaced-apart cross-sectional segments of each railto form said row of individual spaced-apart hooks or loops.
 6. Themethod according to claim 4 wherein said rotating cutter is fixed in atranslational sense with said tubular form being moved past saidrotating cutter in at least a partially encircling relationship thereto,thereby cutting away spaced-apart cross-sectional segments of each railto form said rows of hooks or loops.
 7. The method according to claim 6wherein the steps of bending the base material and cutting awayspaced-apart cross-sectional segments of each rail are performedsubstantially simultaneously with each other.